Patent GB-882098-A (GB)
Title: Organosilicon compounds
IPC: C08G77/00
Filed: 1957-10-03
Abstract: An organofunctional silicon compound is made by admixing a silane of the formula <FORM:0882098/IV (a)/1> or a siloxane of the formula <FORM:0882098/IV (a)/2> wherein R1 is a monovalent hydrocarbon radical, X is a halogen atom or an alkoxy radical, a is an integer greater than 1, and b and c are each 0, 1 or 2, with an aliphatic alcohol and causing, initially esterification of any halogen present in the starting material with elimination of hydrogen halide and, ultimately, alcoholysis of the cyanoalkyl radical in the presence of a strong mineral acid, and separating and recovering the resulting carboalkoxyalkylsilicon compound from the reaction medium.  The starting materials are described and claimed in Specifications 797,792, 847,801 to 847,807 and 855,703.  The carboalkoxyalkylalkoxysilanes are made by adding the alcohol, e.g. methanol, ethanol, propanol or butanol, to the cyanoalkylchlorosilane with stirring, refluxing the mixture, filtering off the NH4Cl formed and removing excess alcohol. The resulting silanes may then be hydrolyzed and condensed to the siloxanes, and in this reaction the carboalkoxyalkyl radical may be preserved or be hydrolyzed to the carboxyalkyl radical.  In the absence of mineral acid the silanes may be hydrolyzed to produce cyclic siloxanes.  The carboalkoxyalkylsilicon compounds may be transesterified, e.g. with any primary or secondary alcohol or hydroxy-terminated polypropylene or polyethylene oxide polymer or phenol, under anhydrous conditions and preferably in the presence of HCl or any perfluoro-organic acid, to produce different esters (see Examples (9) to (13)), transesterification with dihydric alcohols, e.g. ethandiol, propandiol and butandiol, yielding esters of the formula <FORM:0882098/IV (a)/3> and reaction with primary aliphatic or aromatic mono- or di-amines, e.g. butylamine, propylene diamine, and p-aminobenzoic acid, yielding amide derivatives.  The silane esters can be cohydrolyzed with other alkoxy silanes to give silicone oils and resins (see Example 18); the siloxanes can be co-polymerized with other siloxanes (see Example 15) or be saponified with bases to yield the corresponding siloxane acid salts (see Example 17); and the free siloxane acids can be converted, e.g. by reaction with thiomyl chloride, to the corresponding siloxane acid chloride. Examples describe the preparation of (1) b -carbethoxyethyltriethoxy- and b -carbethoxyethylmethyldiethoxysilanes; (2) g -carbethoxypropyltriethoxysilane; (3) g -carbethoxypropylmethyldiethoxysilane; (4, 6) b -carbethoxyethylpolysiloxane; (5, 7, 8) g -carbethoxypropylmethylcyclosiloxanes (tri-, tetra- and pentamers); (19) b -carboxyethylmethylcyclic siloxanes (tri- and tetramers). Uses: for modifying silicones and organic derivatives to produce, e.g. silicone oils which are easily emulsified, oxidation resistant siliconealkyd resins (see Example 16), ultra-violet absorbing aromatic amides (see Example 14), silicone-elastomers and esters of polyalkylene glycols (see Example 12). Specifications 847,802, 847,803, 847,804, 847,805, 847,806, 882,094 and 882,095 also are referred to.  Reference has been directed by the Comptroller to Specification 786,020.